It is true that there is not unanimity in the scientific community over the role of humans in climate change. But with over 97 percent of scientists agreeing that warming is linked to human behavior, science is as close to unanimity as it's likely to get.

Researchers from a number of universities and institutes — including, we'll note, some that do advocacy work — looked at nearly 12,000 peer-reviewed studies released between 1991 and 2011 that contained references to global warming in their abstracts. The team was looking for whether or not the papers addressed the cause of warming; in other words, if people are to blame.

Of those 11,944 papers, the majority didn't take a position on causation. (AGW below is shorthand for scientific term: "anthropogenic global warming.")

But considering only those papers that did suggest a cause, the consensus was overwhelming. Of those, 97.1 percent indicated support for the idea that mankind is responsible for atmospheric warming, primarily through the emission of greenhouse gas.

As time has passed — and as indicators of warming have become more apparent — the number of papers addressing the topic have increased, as have the number of papers suggesting that humans are to blame.

John Cook, lead author of the study, created a video walking through the findings. You can watch it below. But it can be summarized in less than the three-and-a-half minutes Cook spends by simply saying this: There is no debate over climate change. There's only a debate about what, if anything, to do about it.

News reports are focusing on the Germanwings pilot's possible depression, following a familiar script in the wake of mass killings. But the evidence shows violence is extremely rare among the mentally ill.